Systems and methods for mixing an asphalt composition

ABSTRACT

A system and method for monitoring and adjusting a constant flow asphalt manufacturing process includes monitoring the ratios of recycled material to virgin material to minimize costs and adjusting the mixture in real time. Pulverized asphalt shingle (PAS) material may be used as a source of recycled asphalt oil and fed to a mixing drum with real-time monitoring while making real-time adjustments to supplement the asphalt with new asphalt oil to the mixer. The systems and methods may also be used for monitoring, metering, and supplementing recycled aggregate from recycled asphalt pavement (RAP) with new aggregate. The systems and methods may use one or more processors or programmable logic controllers (PLC) to meter the addition of new materials.

RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.13/474,634, filed May 17, 2012, which is based on and claims priority toU.S. Provisional Application Ser. No. 61/486,801 filed May 17, 2011, theentire contents of which are herein incorporated by reference.

FIELD OF THE INVENTION

Aspects of the systems and methods disclosed herein relate to areal-time monitoring and metering of at least one component in aconstant flow process for manufacturing asphalt.

BACKGROUND

In order to minimize costs and the resources necessary to produce newasphalt, recycled asphalt pavement (RAP) may be processed to retrieveaggregate material and asphalt cement or asphalt oil contained therein.In addition, asphalt shingles that make up a significant portion ofresidential roofing materials may also be recycled to produce newasphalt. During the recycling process, some portion of the RAP and therecycled shingles may be recovered as an aggregate material or asasphalt oil.

During the recycling process, the oil content retrieved from therecycled material is not always uniform; therefore, additional virginoil must be incorporated into the new asphalt. As the oil content of newasphalt is regulated and required to fall within specific ranges, theoil content of the new asphalt is sometimes examined after it ismanufactured to determine its conformity to the specified ranges. Thelack of uniformity in the amount of oil recovered from recycledmaterials may result in inadequate new asphalt that may bring aboutexcessive fines and penalties for asphalt producers. Therefore, a needexists for a system to monitor the oil content provided by recycledmaterials and to adjust, automatically, the incorporation of virgin oilas necessary, in real time.

SUMMARY

Systems and methods are provided for monitoring and adjusting theaddition of various asphalt components in near real-time. According toone aspect, a system for monitoring and adjusting an asphalt mixtureincludes at least one processor and a database to store component amountdata for a total oil amount and a total aggregate amount for an asphaltmixture. The total oil amount includes a first oil component and asecond oil component. The system also includes an asphalt mixtureapplication executable by the at least one processor to receivemeasurement data of the first oil component added to the asphalt mixturefrom a sensor. The measurement data identifies a first amount of thefirst oil component. The application also compares the measurement datato the component parameter data for the asphalt mixture, determines thesecond amount of a second oil component based upon the measurement data,and transmits an output signal to a metering device in fluidcommunication with a vessel containing the second oil component, whereinthe second amount of the second oil component is added to the asphaltmixture in near real-time.

In another aspect, a system for monitoring and adjusting an asphaltmixture includes at least one processor and a database to storecomponent amount data for a total aggregate amount and a total oilamount for an asphalt mixture. The total aggregate amount includes afirst aggregate component and a second aggregate component. The systemalso includes an asphalt mixture application executable by the at leastone processor to receive measurement data of the first aggregatecomponent added to the asphalt mixture from a sensor. The measurementdata identifies a first amount of the first aggregate component. Theapplication also compares the measurement data to the componentparameter data for the asphalt mixture, determines the second amount ofa second aggregate component based upon the measurement data, andtransmits an output signal to a metering device in fluid communicationwith a vessel containing the second aggregate component, wherein thesecond amount of the second aggregate component is added to the asphaltmixture in near real-time.

In yet another aspect, a method for monitoring and adjusting an asphaltmixture includes, at at least one processor, receiving measurement dataof a first oil component of an asphalt mixture from a sensor. Themeasurement data identifies a first amount of the first oil component.The method also includes comparing the measurement data to a desiredtotal oil amount, where the desired total oil amount includes the firstoil component and a second oil component. Further, the method includesdetermining a second amount of the second oil component based upon themeasurement data and transmitting an output signal to a metering devicein communication with a vessel containing the second oil component,wherein the output signal adjusts an output of the second oil componentin near real time.

In one aspect, a method for monitoring and adjusting an asphalt mixtureincludes, at at least one processor, receiving measurement data of arecycled oil component of an asphalt mixture from a sensor. Themeasurement data identifies a first amount of the recycled oilcomponent. The method also includes comparing the measurement data to adesired total oil amount, where the total oil amount includes therecycled oil component and a virgin oil component. If the first amountof the recycled oil component is less than the total oil amount, themethod includes determining a second amount of the virgin oil componentbased upon the measurement data, wherein the total amount of the totaloil component equals the sum of the first amount and the second amount,and transmitting a first signal to a metering device in fluidcommunication with a vessel containing the virgin oil component. Thefirst signal causes the second amount of the virgin oil component to beadded to the asphalt mixture in near real time. Alternately, if thefirst amount of the recycled oil component is equal to the total oilamount, the method includes transmitting a second signal to the meteringdevice in communication with the vessel containing the virgin oilcomponent, the second signal stopping the addition of the virgin oilcomponent.

In yet another aspect, a system for monitoring and adjusting an asphaltmixture includes at least one processor and a database to store asphaltmixture amount data for a total oil amount and a total aggregate amountfor an asphalt mixture. The total oil amount includes a recycled oilamount and a virgin oil amount and the total aggregate amount includes arecycled aggregate amount and a virgin aggregate amount.

The system also includes a asphalt mixture application executable by theat least one processor to: receive first measurement data of therecycled oil amount added to the asphalt mixture from a first sensor,receive second measurement data of the recycled aggregate amount addedto the asphalt mixture from a second sensor, compare the firstmeasurement data to the total oil amount, and compare the secondmeasurement data to the total aggregate amount. The asphalt mixtureapplication also determines a virgin oil amount to be added to theasphalt mixture based on the first measurement data and determines avirgin aggregate amount to be added to the asphalt mixture based on thesecond measurement data. The asphalt mixture application transmits avirgin oil output signal to a first metering device in communicationwith a first vessel containing virgin oil, where the virgin oil amountis added to the asphalt mixture in near real-time, and transmits avirgin aggregate output signal to a second metering device incommunication with a second vessel containing virgin aggregate, wherethe virgin aggregate amount is added to the asphalt mixture in nearreal-time.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a block diagram of an automated asphalt component mixingsystem according to one aspect.

FIG. 1B is a block diagram of an automated asphalt component mixingsystem according to another aspect.

FIG. 2 is a plan view layout of an asphalt manufacturing facilityincorporating the asphalt component mixing system according to oneaspect.

FIG. 3 is a plan view layout of an asphalt manufacturing facilityincorporating the asphalt component mixing system according to anotheraspect.

DETAILED DESCRIPTION

The asphalt component mixing systems and methods generally relate to thepreparation and mixing of an asphalt composition. An asphalt compositionmay be produced from a mixture of a number of components, including butnot limited to an aggregate and asphalt oil. Different compositions mayinclude different numbers and ratios of the constituent components. Forexample, one asphalt composition may be a particular ratio of aggregateto oil (e.g. 60% aggregate to 40% oil), while another asphaltcomposition may have a ratio of 75% aggregate to 25% oil. Other asphaltcompositions may include additional components, such as one or moreadditives, and may have different ratios for each component. The oilportion may be divided between virgin oil and recycled oil material suchthat a portion of the total oil is from virgin oil and another portionof the total oil is from recycled oil material.

In particular, the system may be used in a constant-flow manufacturingprocess where the amount of various components within an asphalt mixturethat will become an asphalt composition, may be adjusted in real-time.For example, the system may be used to monitor and manipulate theaddition of recycled asphalt shingle (RAS) material derived fromrecycled roofing shingles or other sources to the mixture, as well asproviding real-time monitoring and metering of new or virgin asphalt oil(VAO) to the mixture.

In one aspect, the amount of VAO added to the mixture is calculated andmetered based, at least in part, on the amount of recycled oil derivedfrom the RAS material, or recycled asphalt pavement (RAP) material,and/or another recycled oil material. In addition, the system andprocess may also provide real-time monitoring and metering of RASmaterial and/or RAP material derived from previously manufacturedasphalt shingles, or pavement to the mixture, as well as monitoring andmetering virgin aggregate additions to the mixture. In one aspect, RAPmaterial may be recycled to reclaim oil and aggregate materials. Assuch, the RAP materials may be included in new asphalt mixtures as onlya reclaimed oil source, only a recycled aggregate source, or both.

As the actual amount of recycled oil, and in one optional embodiment,recycled aggregate, that may be reclaimed from the RAS material, the RAPmaterial, and/or another recycled oil material is not uniform and mayvary at any given moment in the constant-flow process of manufacturingnew asphalt, the system and process allows for the automatic addition ofprecise quantities of VAO to the asphalt mixture. In one aspect, theaddition of VAO to an asphalt mixture composition is achieved usingprogrammable logic controllers (PLC) or other computing devices tocontrol the operation of one or more pumps in fluid communication withone or more vessels containing VAO based on sensor data identifying theamount of recycled oil material delivered for the asphalt mixturecomposition. In various other aspects, the system may be incorporatedinto new or existing asphalt manufacturing facilities.

In one aspect, as shown in FIG. 1A, the asphalt mixing system 100Aincludes a aggregate source 102, a reclaimed oil (RO) source 104 incommunication with an reclaimed oil (RO) sensor 106, a VAO source 108 incommunication with a VAO pump 110, a mixing drum 112, various deliverysystems 114A-114C, and a computing device 116.

The aggregate source 102 includes aggregate material. Aggregategenerally refers to a broad category of coarse particulate material asunderstood by one having ordinary skill in the art. The aggregate mayinclude sand, gravel, crushed stone, slag, recycled concrete, and/orgeosynthetic aggregates, among others. The asphalt mixing system 100 maybe used with any suitable aggregate material. Although shown as a singlesource, the aggregate source 102 may be a single source or distributedsources, such as one or more cold-feed bins, storage bins, storagedrums, and/or storage silos. The aggregate source 102 may also includeaggregate obtained directly from a primary aggregate source, such as aquarry or an off-site recycling facility. In one embodiment, theaggregate includes recycled aggregate separated from RAP or otherrecycled material

The RO source 104 includes asphalt oil and/or asphalt oil materialrecovered from RAP, the RAS material, and/or another recycled orreclaimed oil material. The RO material is some portion (including fromzero to 100%) of the total asphalt oil delivered to the mixing drum 112.An amount of RO and an amount of VAO make up a total amount of asphaltoil delivered to the mixing drum. For example, asphalt oil may beextracted from the RAP and separated from the recycled aggregate.Similarly, asphalt oil may be derived or extracted from ground asphaltshingles. Although shown as a single source, the RO source 104 materialmay be a single source or distributed sources, such as one or morecold-feed bins, storage bins, storage drums, and/or storage silos. TheRO source 104 may also refer to any of the various tools and machineryused for recycling pavement, shingles, and/or another asphalt oilmaterial.

The RO source 104 is in communication with the RO sensor 106 thatmeasures the amount of RO that is being delivered to the asphaltmixture. The RO sensor 106 may be, for example, a weight-determiningsensor, such as a load cell, a weigh depletion sensor, avolume-determining sensor, or another sensor to determine the amount ofreclaimed oil material delivered to the mixing drum 112. In one aspect,the RO sensor 106 measures the weight of the reclaimed oil material fromthe RO source delivered to the mixing drum 112. In another aspect, theRO sensor 106 measures the volume of liquid reclaimed oil materialdelivered to the mixing drum 112. In another aspect, the RO sensor 106determines the volume, weight, or other parameter of the reclaimed oilmaterial blown, pumped, or otherwise delivered to the mixing drum 112.

In one aspect, the delivery systems 114A and 114B include at least onesensor or device to weigh the material transported by the deliverysystems. For example, one or more transducers, such as load cells, maybe incorporated into or at least in communication with the deliverysystems 114A and 114B. As such, the load cells, can measure the weightof the materials transported by the delivery systems 114A and 114B. Oneor more load cells may be placed along the entire length of the deliverysystems 114A-114B, or alternately, the one or more load cells may bepositioned at particular locations along the delivery systems.

In other aspects, the RO may not be completely separate from recycledaggregate material. For example, asphalt oil may not be completelyseparated from aggregate or other material, including dust, derived fromrecycled shingles. As the oil content of the roofing shingles may beknown or determined prior to recycling, the RO sensor 106 may determinethe weight of the oil-containing RAS material that is being delivered tothe mixing drum 112. In various other aspects, the RO sensor may captureother parameters of the RO material. As such, the RO sensor 106 capturesdata relevant to determining the amount of RO provided to the mixingdrum 112.

The VAO source 108 is a source of virgin asphalt oil used in themanufacture of new asphalt. The VAO is some portion (including from zeroto 100%) of the total asphalt oil delivered to the mixing drum 112. Anamount of VAO and an amount of RO make up a total amount of asphalt oildelivered to the mixing drum. In one example, the VAO is used tosupplement and/or augment the volume of RO material delivered to mixingdrum 112.

The VAO pump 110 controls the amount of VAO delivered to the mixing drum112 from the VAO source 108. The VAO pump 110 can increase or decreasethe amount of VAO delivered to the mixing drum 112 in real-time. Forexample, an asphalt mixture having an oil content of approximately 20%may be composed of 80% aggregate, 10% RO, and 10% virgin oil. The virginoil may used or the amount of virgin oil may be increased, if the oilcontent of the recycled oil material is non-uniform, unknown,insufficient, or if is determined the actual amount of RO beingdelivered to the mixing drum 112 is less than the calculated amount ofRO that was initially to be delivered to the mixing drum. The actualratio of RO to VAO can be varied in real time by the asphalt mixingsystem 100A.

The various input components used in an asphalt mixture are delivered tothe mixing drum 112 by delivery systems 114A-C. The delivery systems114A-C may be any mechanism suitable for transporting the materials fromthe respective sources 102, 104, and 108 to the mixing drum 112, such asone or more of an auger conveyor, a pneumatic conveyor system, aconveyor belt, a pump, one or more pipes, or one or more other deliverymechanisms. For example, the delivery systems 114A and 114B may includeone or more conveyor belts and/or one or more auger conveyors.Similarly, the delivery system 114C may be any delivery system suitablefor transporting the VAO, including but not limited to various lengthsof piping. For example, the delivery system for the VAO may beconfigured for transferring liquids. Other delivery systems fortransporting materials and systems for holding and/or storing materialsmay be used, including but not limited to hoppers.

In one embodiment, the operation of the VAO pump 110, and therefore theamount of VAO provided to the asphalt mixture, is controlled by thecomputing device 116 or another control system. In operation, thecomputing device 116 receives data from various components, such as theRO sensor 106, to continuously monitor the amounts of materialsdelivered to and/or added to the mixing drum 112. In response to changesin the amount of materials delivered to and/or added to the mixing drum112, the computing device 116 recalculates the amount of the othermaterials, in real-time, to be delivered to and/or added to the mixingdrum to achieve a particular product mixture.

For example, the computing device 116, may receive input from the ROsensor 106 to determine the actual amount of RAS material or other ROmaterial being delivered to and/or added to the mixing drum 112. As thecomputing device 116 determines the amount of the RAS material that isdelivered to the mixing drum 112, it simultaneously adjusts the pump 110to modify and meter the flow of VAO delivered from the VAO source 108 tothe mixing drum 112. The computing device 116 therefore, causes theamount of VAO pumped in to the mixing drum 112 to increase or decreasedepending on the actual, measured amount of RAS material or other ROmaterial that is delivered to and added to the mixing drum 112.

Thus, the computing device 116 retrieves data identifying the desiredamount of the components (aggregate, RO material, and/or VAO) to bedelivered to the mixing drum 112 for a particular asphalt mixture from adatabase or other data storage location, including the memory 120, andreceives data from one or more sensors, including the RO sensor 106,indicating the actual amount of the components (aggregate, RO material,and/or VAO) delivered to the mixing drum. The desired amounts of ROmaterial, VAO, and aggregate may be, for example, pre-determined orpre-defined amounts for an asphalt mixture or amounts stored in adatabase or calculated by the computing device 116 for an asphaltmixture. The computing device 116 also determines modifications to oneor more delivery systems 114A-C to meter (adjust) the amount of materialfrom one or more sources, including at least the VAO pump 110 to pumpVAO from the VAO source 108, and transmits one or more signals to theone or more delivery systems or sources 102, 104, 108, including the VAOpump, to meter the amount of material, including at least VAO, deliveredto the mixing drum 112. In response to receiving one or more signalsfrom the computing device 116, the receiving delivery system 114A-C orsource 102, 104, and 108, including at least the VAO pump 110, meters(adjusts) the amount of material delivered by the delivery system to themixing drum 112.

By way of example and not limitation, the computing device 116 mayretrieve data for a particular asphalt composition that requires 60%aggregate by weight and 40% oil by weight. The computing device 116 alsomay retrieve or calculate the optimal delivery or flow rate for theaggregate and oil to achieve the desired composition. During themanufacturing process, the computing device 116 receives data from theRO sensor 106 indicating that the delivery or flow of RO material andtherefore RO is insufficient to produce an asphalt composition that is40% weight by volume. For example, the delivery of the RO material maybe decreased or stopped. In response, the computing device 116 generatesand transmits a signal to the VAO pump 110 to initiate or increase thedelivery of VAO to the mixing drum 112 to compensate for theinsufficiently delivered RO material. The VAO pump 110 receives thesignal and initiates or increases the output of VAO from the VAO source108 to be delivered to the mixing drum 112.

In another example, the computing device 116 may receive data from theRO sensor 106 indicating that the flow of RO material is increasing oris otherwise sufficient to deliver the necessary amount of RO to themixing drum. In response, the computing device 116 generates andtransmits a signal to the VAO pump 110 to decrease or halt the deliveryof VAO to the mixing drum 112. The VAO pump 110 receives the signal anddecreases or halts output of VAO from the VAO source 108 to be deliveredto the mixing drum.

In other examples, the computing device 116 may receive data from theaggregate sensor 126 regarding the delivery or flow of recycledaggregate material from an aggregate source 102 to the mixing drum 112and generate signals that are received at the aggregate source ordelivery system 114A to increase or decrease the amount of virginaggregate provided to the mixing drum. In response, the aggregate source102 or delivery system 114A increases or decreases the amount ofaggregate delivered to the mixing drum 112. The computing device 116 mayreceive data from one or more sensors and adjust the flow of one or morecomponents in real-time, during the manufacturing process.

In one aspect, the computing device 116 includes at least one processor118 and memory 120. For example, the computing device 116 may be aprogrammable logic controller (PLC), a personal computer, workstation,server, or mobile device. The processor 118 is a hardware device thatprocesses software, other machine-readable instructions, retrieved data,and/or received data. The memory 120 may store the software or othermachine-readable instructions and data. The memory 120 may includevolatile and/or non-volatile memory. The memory 120 may comprise adatabase to store data identifying the desired amounts of RO material,VAO, and aggregate for an asphalt mixture, such as in pre-determined orpre-defined amounts, and a total amount of oil comprised of one or moreof virgin oil and recycled oil material. The computing device 116 mayfurther include various hardware and accompanying software componentsthat may be configured for receiving data from one or more of theasphalt component sources 102, 104, 108, and/or one or more sensors,such as the RO sensor 106.

Additionally, the computing device 116 may also include a communicationsystem to communicate with one or more components of the asphalt mixingsystem 100A, such as the RO sensor 106 and optionally other sensors,sources, and/or delivery systems, over a communication network viawireline and/or wireless communications, such as through the Internet,an intranet, and Ethernet network, a wireline network, a wirelessnetwork, and/or another communication network of the asphalt mixingsystem. The computing device 116 may further include a display (notshown) for viewing data or one or more user interfaces (UI), such as acomputer monitor, and an input device (not shown), such as a keyboard ora pointing device (e.g., a mouse, trackball, pen, touch pad, or otherdevice) for entering data and navigating through data, including images,documents, structured data, unstructured data, HTML pages, other webpages, and other data.

The computing device 116 may include a database (not shown) and/or isconfigured to access the database. The database may be a generalrepository of data including, but not limited to, user data, asphaltcomposition mixture data, or any other data related to asphaltproduction, including data regarding the type and amount of components(aggregate, RO material, and/or VAO) in various asphalt compositions,operating parameters of the various components at an asphaltmanufacturing plant, such as processing capacities and rates anddelivery system capacities and rates. For example, the database storesdata identifying the desired amounts of RO material, VAO, and aggregatefor an asphalt mixture, such as in pre-determined or pre-definedamounts. The database may include memory and one or more processors orprocessing systems to receive, process, query and transmitcommunications and store and retrieve such data. In another aspect, thedatabase may be a database server.

According to one aspect, the computing device 116 includes a computerreadable medium (“CRM”) 122, which may include computer storage media,communication media, and/or another available media medium that can beaccessed by the processor 118. For example, CRM 122 may includenon-transient computer storage media and communication media. By way ofexample and not limitation, computer storage media includes memory,volatile media, nonvolatile media, removable media, and/or non-removablemedia implemented in a method or technology for storage of information,such as machine/computer readable/executable instructions, datastructures, program modules, or other data. Communication media includesmachine/computer readable/executable instructions, data structures,program modules, or other data and includes an information deliverymedia or system. The CRM 122 may store executable instructions toimplement an asphalt constituent mixture application 124 to implementthe sensor monitoring and VAO pump operation to meter the VAO. Forexample, the asphalt constituent mixture application 124 is loaded orstored on the CRM in one example. Generally, program modules includeroutines, programs, instructions, objects, components, data structures,etc., that perform particular tasks or implement particular abstractdata types.

The asphalt mixture application 124 receives sensor data from one ormore of the sensors, including the RO sensor 106. The sensor dataidentifies measured amounts of material. The asphalt mixture application124 compares the sensor data to pre-defined or calculated dataidentifying desired amounts of material, determines adjustment amounts(increases, decreases, initiations, or halts) for the VOA to be added tothe asphalt mixture, and controls sending one or more signals to the VOApump 110 to adjust the output of the amount of VOA delivered from theVOA source 108 to the mixing drum 112. For example, one or more of thedesired amounts are stored as parameters identifying pre-defined orpre-determined amounts of RO material and/or VOA and/or aggregate to bedelivered to the mixing drum 112 for the asphalt mixture.

In one example, the asphalt mixture application 124 retrieves thepre-defined component amount data from the database. The pre-definedcomponent amount data identifies pre-defined or pre-determined amountsof RO material and/or VOA and/or aggregate to be delivered to the mixingdrum 112 for the asphalt mixture. The asphalt mixture application 124receives the measured amount of RO material from the RO sensor andcompares the measured amount of RO material to the pre-defined amount ofRO material. The asphalt mixture application 124 determines an amount ofthe VOA needed for the asphalt mixture based upon the comparison of themeasured amount of RO material to the pre-defined amount of RO material,such as more, less, none, or at least some. The asphalt mixtureapplication 124 transmits a signal to the VO pump 110 to adjust(initiate, increase, halt, or decrease) a pumped amount of the VOApumped from the VAO source 108 to be the determined amount.

In another example, the asphalt mixture application 124 receivesmeasurement data of a first oil component added to the asphalt mixturefrom a sensor. The measurement data identifies a first amount of thefirst oil component. The application also compares the measurement datato the component parameter data for the asphalt mixture, determines thesecond amount of a second oil component based upon the measurement data,and transmits an output signal to a metering device in fluidcommunication with a vessel containing the second oil component, whereinthe second amount of the second oil component is added to the asphaltmixture in near real-time.

In one aspect, the computing device 116 with a database, a processor118, and an asphalt mixture application 124 collectively are referred toas a control system.

The VAO pump 110 has circuitry, hardware, and/or software to receive oneor more signals from the computing device 116 and increase, decrease,initiate, or halt the delivery or flow of VAO from the VAO source 108 inresponse to the one or more signals. Optionally, the aggregate source102, RO source 104, delivery system 114A, and/or delivery system 114Boptionally each have circuitry, hardware, and/or software to receive oneor more signals from the computing device 116 and increase, decrease,initiate, or halt the delivery or flow of material from respectivesources to the mixing drum in response to the one or more signals.

FIG. 1B depicts another embodiment of the asphalt mixing system,indicated as 100B. In this embodiment, the computing device alsoreceives data regarding the amount of aggregate and VAO actuallydelivered to the mixing drum 112, from an aggregate sensor 126 and avirgin asphalt oil (VAO) sensor 128. For example, the aggregate sensor126 may be one or more load cells, weigh depletion sensors, other weightdetermining sensors, or another type of sensor. The VAO pump 110 may beused to meter the VAO transported by the delivery system 114C, and theVAO sensor 128 may be incorporated along the delivery system 114C toprovide additional data regarding the VAO pumped to the mixing drum 112.The VAO sensor 106 may be any suitable sensor or meter, including butnot limited to a flow meter, to precisely measure the volume of VAOdelivered to the mixing drum 112.

By also monitoring the aggregate and VAO delivered to the mixing drum112, a user of the asphalt mixing system 100 may ensure that the desiredratios of aggregate-to-oil delivered to the mixing drum 112 aremaintained. The user may also be able to identify any deficiencies inthe materials provided to the mixing drum 112, which may indicate ablockage or broken machinery in the asphalt plant.

In addition, by monitoring all of the materials intended to enter themixing drum 112, the user may further change the composition of theasphalt mixture, in real time, to increase or decrease theaggregate-to-oil ratio of the mixture delivered to the mixing drum 112.

Referring now to FIG. 2, a plan view layout of an asphalt manufacturingfacility 200 incorporating the asphalt mixing system 100 is shown. Anaggregate source 102 is in communication with a delivery system 202,such as a conveyor belt, that transports aggregate material to a dryer204, such as a drying drum. Similarly, aggregate obtained from a RAPsource 206, optionally is transported by another delivery system 208,such as a conveyor belt or auger conveyor, to the dryer 204. In oneaspect, the virgin aggregate and recycled aggregate derived from RAP maybe transported by the same delivery system. The aggregate source 102 andthe RAP source 206 each may include one or more cold feed bins or otherstorage or holding structures containing the respective aggregatematerial. The cold feed bins are configured to drop quantities of theaggregate and the RAP material onto the respective delivery systems 202and 208. In one aspect, each delivery system 202 and 208 includes atleast one load cell, weigh depletion sensor, or other sensors 210 and212, respectively to measure the amount of aggregate and RAP materialprovided to the dryer 204. The RAP source 206, the delivery system 208,and the sensor 212 are optional in some embodiments.

The dryer 204 heats the aggregate material to remove moisture andimprove subsequent bonding between the aggregate and the asphalt oil inthe mixing drum 112. The dryer 204 may be any dryer or drying drumsuitable for heating and drying the aggregate material.

While drying, heated air blown into the dryer 204 extracts large amountsof dust and sand from the heated aggregate mix and carries it to areceiver/blower 214, such as a baghouse, where the air is filtered andthe fine particles are collected. These particles are fed back into themixing drum 112, as generally indicated by 216, to become part of thenew asphalt mix. Any suitable configuration for the receiver/blower 214may be used. The aggregate material remaining in dryer 204 istransferred to the mixing drum 112 via another delivery system 218.

One source of asphalt oil for the asphalt mixture is oil reclaimed fromRAS material. In one aspect, roofing shingles are shredded or ground ina shredder or grinder 220. The RAS material is passed through theshredder or grinder 220 in one or more passes. In one example, during afirst pass, the RAS material is reduced to pieces approximately ¼″ by¼″. In a second pass, the RAS material is further reduced toapproximately ⅛″ by ⅛″. Though in other instances, the RAS material maybe ground or shredded in a single pass. In one example, the ground orshredded RAS material is less than approximately ⅛″. In another example,the ground or shredded RAS material is between approximately 1/16″ to½″.

Similar to the aggregate material, the shredded or ground RAS materialis carried to a receiver/blower 222, such as a baghouse, where the dustis filtered and collected. In one aspect, the entirety of the RASmaterial is filtered though the receiver/blower 222, before beingcarried to the mixing drum 112. In another aspect, a cyclone separator224 is used is used to remove larger pieces of the RAS material bycyclonic separation, before the fine dust particles are carried to thereceiver/blower 222. The larger pieces are carried by a delivery system226 to the mixing drum 112. The delivery system 226 may be configured asa conveyor belt, a hopper-belt conveyor, an auger conveyor, or apneumatic conveyor, among others.

Due to the small particle size of the pulverized (e.g. ground orshredded) RAS material, there is a potential for the RAS material toclump, thereby by causing intermittent or partial blockages of thedelivery system 226. For example, the RAS material may clog anauger-based delivery system. Therefore, despite weighing the RASmaterial after grinding or shredding, the amount of RAS materialactually delivered to or being fed into the mixing drum 112 may not be aconstant value and may vary from the calculated or pre-determined orpre-defined value. As such, the amount of RO delivered to the mixingdrum 112 may vary.

To account for variance in the amount of RAS material delivered to themixing drum 112, the amount of RAS material is measured by one or moresensors, such as the RO sensor 106. In one embodiment, the RO sensor 106is a weigh depletion sensor or load cell that determines the weight ofthe RO material delivered to the mixing drum 112 For example, a weighdepletion sensor, such as one or more load cells, measures or determinesweights of a storage or holding bin or device in which material isstored or held and determines the amount of material dispersed from thebin or device by measuring or determining the change in weight or massof the bin or device. In this embodiment, the weight and oil content ofthe RAS material is known or at least determined prior to processing theshingles. Subsequent measurements of the weight of the RAS material maybe used to determine the actual amount of RAS material delivered to themixing drum, and therefore determine the amount of RO delivered to themixing drum 112. While it is believed that weight depletion is onemethod of determining the amount of RAS delivered to the mixing drum,other methods may be used, including but not limited to, monitoring thedepletion level within a pulverized RAS cold-feed storage bin, weighingmaterial on or passing over or through the delivery system, etc.

In one aspect, the data from the RO sensor 106 is transmitted to thecomputing device 116, located in a control area 228, such as a building.Although shown in a detached control area 228, the computing device 116may be located in any suitable location. The computing device may beconfigured to receive and transmit data by a wired connection or by awireless connection to the one or more sensors, such as the RO sensor106.

In one embodiment, the computing device 116 is a programmable logiccontroller (PLC) 230 that has been specially programmed to adjust theoutput of the VAO pump 110, in real-time, in response to the datareceived from the RO sensor 106. For example, when the PLC 230determines the weight and therefore amount of the RAS material deliveredto and entering the mixing drum 112 decreases or is otherwiseinsufficient to provide the desired amount of RO, the PLC automaticallyand simultaneously adjusts the output of the VAO pump 110 to increasethe flow of VAO from the VAO storage tank(s) 232 or other VAO sourcethrough the delivery system 234 and into the mixing drum 112.Conversely, when the PLC 230 determines that the weight and thereforeamount of the RAS material delivered to and entering the mixing drum 112is increasing or is otherwise sufficient to provide the desired amountof RO, the PLC automatically and simultaneously adjusts the output ofthe VAO pump 110 to decrease, maintain, or stop the flow, as needed, ofVAO from the VAO storage tank(s) 232 or other VAO source into the mixingdrum 112. Therefore, to maintain the desired oil content in the mixingdrum 112, the amount of VAO is automatically varied, in real-time, toaccount for variance in the amount of RO delivered to and entering theasphalt mixture in the mixing drum 112. The desired amounts of RO, VAO,and aggregate may be, for example, pre-determined or pre-defined amountsfor an asphalt mixture or amounts calculated by the PLC 230 for anasphalt mixture.

Thus, the PLC 230 retrieves data identifying the desired amounts of thecomponents (aggregate, RO material, and/or VAO), such as from adatabase, to be delivered to the mixing drum 112 for a particularasphalt mixture from a database or other data storage location,including memory of to the PLC and receives data from one or moresensors, including the RO sensor 106, indicating the actual amounts ofthe components (aggregate, RO material, and/or VAO) delivered to themixing drum. The PLC 230 also determines modifications to one or moredelivery systems 202, 208, 218, 226, and 234 to meter (adjust) theamount of material from one or more sources, including at least the VAOpump 110 to pump VAO from the VAO source 232, and transmits one or moresignals to the one or more delivery systems or sources 102, 104, 108,including at least the VAO pump 110 to meter the amount of VAO materialdelivered to the mixing drum 112. In response to receiving the signalfrom the PLC 230, the receiving delivery system 202, 208, 218, 226, 234or source 102, 206, 220, and 232, including at least the VAO pump 110,meters (adjusts) the amount of material delivered by the delivery systemto the mixing drum 112.

By way of example and not limitation, the PLC 230 may retrievepre-defined or pre-determined or pre-defined data identifying amountsfor a specific asphalt composition (mixture) that requires 75% aggregateby weight and 25% oil by weight. The PLC 230 also may retrieve orcalculate the optimal flow or delivery rate for the aggregate and oil toachieve the desired composition. During the manufacturing process, thePLC 230 receives data from the RO sensor 106 indicating that the flow ofRO material and therefore the amount of RO is decreasing or isinsufficient to produce an asphalt composition that is 25% weight byvolume. In response, the PLC 230 generates and transmits a signal to theVAO pump 110 to initiate or increase the delivery of VAO to the mixingdrum 112. For example, the signal may indicate the VAO pump 110 mustincrease output by 50%. The VAO pump 110 receives the signal andinitiates or increases the output of VAO accordingly.

In another example, the PLC 230 may receive data from the RO sensor 106indicating that the flow of RO material is increasing or is otherwisesufficient to deliver the necessary amount of RO to the mixing drum. Inresponse, the PLC 230 generates and transmits a signal to the VAO pump110 to decrease or halt the delivery of VAO to the mixing drum 112. Forexample, the signal may indicate the VAO pump 110 must decrease theoutput of VAO by 50%. The VAO pump 110 receives the signal and decreasesthe output of VAO accordingly.

In other examples, the PLC 230 may receive data from the sensor 212regarding the flow of recycled aggregate material from the RAP source206 to the mixing drum 112 and generate signals that are received at theaggregate source 102 or delivery system 202 to increase or decrease theamount of virgin aggregate provided to the mixing drum. The aggregatesource 102 or delivery system 202 receives the signal and adjusts theamount of aggregate delivered to the mixing drum 112 accordingly. ThePLC 230 may receive data from one or more sensors and adjust the flow ofone or more components in real-time, during the manufacturing process.

In other embodiments, the PLC 230 may receive data from additionalsensors such as the aggregate sensor 126, the VAO sensor 128, and a RAPsensor 212. For example, the aggregate sensor 126 or the RAP sensor 212may be load cells or weigh depletion sensors to weigh the respectiveaggregate materials delivered to the asphalt mixture or other sensortypes to determine an amount of material delivered to the asphaltmixture. Moreover, although RAP may be used as an aggregate constituentto reduce the amount of virgin aggregate in the asphalt mixture, RAP maycontain a significant amount of RO, which may impact the oil content ofthe asphalt mixture. Therefore, in one aspect, the computing device 116may rely upon input from the RAP sensor 212 to adjust the input ofvirgin aggregate and/or VAO due to the aggregate and/or ROcontributions, respectively, of the RAP.

By way of example and not limitation, the weight of the RAP may bedetermined as it passes the RAP sensor 212 before it is ultimatelydelivered to the mixing drum 112. The RAP sensor 212 measures the weightof the RAP delivered by the delivery system 208 and transmits the datato PLC 230, where the amount of virgin aggregate from the aggregatesource 102 is adjusted accordingly. In one example, RAP is fed into thedryer 204 by the delivery system 208. In another example, RAP isdelivered directly to the mixing drum 112 by the delivery system 208 andis not fed into the dryer 204.

In an embodiment, the PLC 230 therefore monitors and adjusts, inreal-time, the combined aggregate input consisting of virgin aggregateand optionally recycled aggregate from the RAP, as well as the combinedasphalt oil input consisting of oil contained in the RAS material andthe VAO to produce a new asphalt mixture composition. As a result, thenew asphalt mixture composition has maximized quantities of recycledmaterial from the RAS and optionally RAP, while minimizing the amount ofhigher-cost virgin materials, such as the VAO and virgin aggregate.Moreover, the PLC 230 may be reprogrammed quickly and efficiently tomodify the aggregate-to-oil ratio of the asphalt mixture, in response tolegislative, industry, or specific application demands. For example, inone embodiment where the RAP material is reclaimed only as an aggregatesource, the amount of VAO delivered to the mixing drum 112 is based onthe availability of RO from the RAS. Conversely, in an embodiment whereoil is reclaimed from the RAP material, the amount of VAO delivered tothe mixing drum 112 is based on the total amount of recycled oilreclaimed from the RAS and RAP materials.

After the desired quantities of aggregate and oil have been delivered tothe mixing drum 112, new asphalt is produced and transferred to one ormore storage silos 236A-C by the delivery system 238 for storage. Theasphalt mixing system 100 may be configured to vary the aggregate-to-oilratio of the new asphalt during production, such that multiple andvaried compositions of asphalt may be produced in rapid succession andstored in the one or more storage silos 236A-C.

FIG. 3 depicts another asphalt manufacturing facility 300 incorporatingthe asphalt mixing system 100. In this embodiment, the pulverized (e.g.ground or shredded) RAS material is transported predominately by apneumatic system, indicated generally as 302. The pneumatic system 302is configured to maximize the RAS material provided to the mixing drum112 and minimize the potential for clogging. Regardless of the manner inwhich the RAS material is transported, the amount of RAS materialdelivered to the mixing drum 112 is monitored in real-time.

It is believed that the present disclosure and many of its attendantadvantages will be understood by the foregoing description, and it willbe apparent that various changes may be made in the form, construction,and arrangement of the components without departing from the disclosedsubject matter or without sacrificing all of its material advantages.The form described is merely explanatory, and it is the intention of thefollowing claims to encompass and include such changes.

While the present disclosure has been described with reference tovarious embodiments, it will be understood that these embodiments areillustrative and that the scope of the disclosure is not limited tothem. Many variations, modifications, additions, and improvements arepossible. More generally, embodiments in accordance with the presentdisclosure have been described in the context of particularimplementations. Functionality may be separated or combined in blocksdifferently in various embodiments of the disclosure or described withdifferent terminology. These and other variations, modifications,additions, and improvements may fall within the scope of the disclosureas defined in the claims that follow.

Those skilled in the art will appreciate that variations from thespecific embodiments disclosed above are contemplated by the invention.The following invention should not be restricted to the aboveembodiments, but should be measured by the following claims.

The invention claimed is:
 1. A method of preparing an asphalt mixturecomprising a recycled oil component, said method comprising: shreddingor grinding roofing shingles in a shredder or grinder to yield apulverized recycled asphalt shingle material, wherein said roofingshingles are reduced to a particle size of less than approximately ⅛″,wherein said pulverized recycled asphalt shingle material comprises anamount of recycled oil; delivering said pulverized recycled asphaltshingle material to a mixing drum, wherein a sensor measures the amountof recycled oil from said pulverized recycled asphalt shingle materialdelivered to the mixing drum; delivering an aggregate material to saidmixing drum; and delivering an optional amount of virgin asphalt oil tosaid mixing drum based upon the amount of recycled oil measured by saidsensor and delivered to the mixing drum to achieve a total desired oilamount in said mixing drum, wherein the total desired oil amountcomprises the recycled oil amount and optional virgin oil amount;thereby producing said asphalt mixture.
 2. The method of claim 1,wherein said roofing shingles are shredded or ground in a single passthrough said shredder or grinder to reduce said roofing shingles to saidparticle size of less than approximately ⅛″.
 3. The method of claim 1,further comprising increasing or decreasing the amount of virgin asphaltoil delivered to said mixing drum depending upon the amount of recycledoil measured by said sensor.
 4. The method of claim 1, wherein saidsensor is a load cell or weigh depletion sensor.
 5. The method of claim1, wherein said aggregate comprises ground recycled asphalt pavement. 6.The method of claim 1, wherein said aggregate comprises virginaggregate.
 7. The method of claim 1, further comprising monitoring andadjusting the asphalt mixture, said method comprising: at least oneprocessor: receiving measurement data of the recycled oil amount fromsaid sensor; comparing the measurement data to component amount data forthe asphalt mixture stored in a memory accessible by the at least oneprocessor, the component amount data identifying the total desired oilamount, wherein the total desired oil amount comprises the recycled oilamount and virgin oil amount; determining an amount of virgin oil basedupon a comparison between the measurement data and component amount datafor the asphalt mixture, such that the recycled oil amount and virginoil amount equal the total desired oil amount; and transmitting anoutput signal to a metering device in communication with a vesselcontaining the virgin oil, wherein the output signal adjusts an outputof virgin oil to be added to the asphalt mixture in the mixing drum. 8.The method of claim 7, wherein the output signal increases the amount ofvirgin oil.
 9. The method of claim 7, wherein the output signaldecreases the amount of virgin oil.
 10. The method of claim 7, whereinwhen the amount of recycled oil is equal to the total desired oilamount, said method further comprising: transmitting a second outputsignal to the metering device to stop the addition of virgin oil to themixing drum.
 11. The method of claim 7, wherein the metering devicecomprises a pump.
 12. The method of claim 1, wherein said pulverizedrecycled asphalt shingle material is delivered to said mixing drum by atleast one of an augur delivery system, a pneumatic delivery system, or aconveyor-belt delivery system.
 13. The method of claim 1, wherein saidpulverized recycled asphalt shingle material is delivered directly tosaid mixing drum from said shredder or grinder.
 14. A method ofpreparing an asphalt mixture comprising a recycled oil component, saidmethod comprising: shredding or grinding roofing shingles in a shredderor grinder to yield a pulverized recycled asphalt shingle material,wherein said roofing shingles are reduced to a particle size of lessthan approximately ⅛″, wherein said pulverized recycled asphalt shinglematerial comprises an amount of recycled oil; delivering said pulverizedrecycled asphalt shingle material to a mixing drum, and monitoring theamount of recycled oil delivered to said mixing drum in real-time;delivering an aggregate material to said mixing drum; and delivering anoptional amount of virgin asphalt oil to said mixing drum based upon theamount of recycled oil delivered to said mixing drum in real-time toachieve a total desired oil amount in said mixing drum, wherein thetotal desired oil amount comprises the recycled oil amount and optionalvirgin oil amount; thereby producing said asphalt mixture.
 15. Themethod of claim 14, wherein said roofing shingles are shredded or groundin a single pass through said shredder or grinder to reduce said roofingshingles to said particle size of less than approximately ⅛″.
 16. Amethod of preparing an asphalt mixture comprising a recycled oilcomponent, said method comprising: shredding or grinding roofingshingles in a shredder or grinder to yield a pulverized recycled asphaltshingle material, wherein said roofing shingles are reduced to aparticle size of less than approximately ⅛″, wherein said pulverizedrecycled asphalt shingle material comprises an amount of recycled oil;delivering said pulverized recycled asphalt shingle material to a mixingdrum; delivering an aggregate material to said mixing drum; anddelivering an optional amount of virgin asphalt oil to said mixing drum,thereby producing said asphalt mixture; said method further comprisingmonitoring and adjusting said asphalt mixture, comprising: at least oneprocessor: receiving measurement data of the recycled oil amount from asensor; comparing the measurement data to component amount data for theasphalt mixture stored in a memory accessible by the at least oneprocessor, the component amount data identifying a total desired oilamount, wherein the total desired oil amount comprises the recycled oilamount and virgin oil amount; determining an amount of virgin oil basedupon a comparison between the measurement data and component amount datafor the asphalt mixture, such that the recycled oil amount and virginoil amount equal the total desired oil amount; and transmitting anoutput signal a metering device in communication with a vesselcontaining the virgin oil, wherein the output signal adjusts an outputof virgin oil to be added to the asphalt mixture in the mixing drum. 17.The method of claim 16, wherein said roofing shingles are shredded orground in a single pass through said shredder or grinder to reduce saidroofing shingles to said particle size of less than approximately ⅛″.18. The method of claim 16, wherein the output signal increases ordecreases the amount of virgin oil.
 19. The method of claim 16, whereinwhen the amount of recycled oil is equal to the total desired oilamount, said method further comprising: transmitting a second outputsignal to the metering device to stop the addition of virgin oil to themixing drum.